The 2018-19 Premier League season is upon us. Kickoff, believe it or not, is just days away. To get you set for the planet’s most enthralling 38-game soccer circuit, Yahoo Sports’ Premier League XI will delve into the 11 most compelling questions ahead of the coming campaign. Next, we go back to Manchester, where trouble is brewing.

It is never Jose Mourinho’s fault. Or, at least, never in the mind of Jose Mourinho.

Mourinho, unprompted: "Two beautiful goals. But the referees, they come by mistake. They were called by the baseball federation. They thought it was a baseball game. They arrived here, it was soccer, they had to be in a soccer game. And it was good fun."

It was either infuriating or hilarious, depending on your perspective, and it was microcosmic of the Mourinho summer 2018 experience. He has turned into the notorious Third Season Mourinho – into Jose The Grouch. He has lashed out at everything from the length of the offseason to the vanity of United’s U.S. tour to the club’s transfer policy.

It is all inescapably ominous, for a few reasons. One, of course, is the flameout precedent. Another is that Manchester United might just not be very good.

Manchester United’s on-field problems

United was closer to sixth than first. More importantly, advanced statistical models screamed “overachievers,” and pegged the Red Devils as the Premier League’s sixth-best team. They exploded in August and September, then stagnated. From Oct. 1 onward, per Understat, their Expected Goal differential was a meager plus-2.1 – behind Crystal Palace, nearer West Brom on the negative end than Arsenal on the positive end.

The issues were a permeable midfield and defense constantly bailed out by a 99th-percentile David De Gea season; and a constricted, malfunctioning attack. Mourinho didn’t deviate from his customary conservative approach. He did, however, stuff considerable attacking talent into midfield and ask it to perform defensive tasks. When players like Paul Pogba and Jesse Lingard couldn’t, a substandard back four were exposed. Antonio Valencia and Ashley Young are converted wingers. Chris Smalling and Phil Jones couldn’t win enough individual duels. Eric Bailly made just 13 league appearances.

Mourinho’s response was to rein in his midfield catalysts even more, suppressing their creativity. He handed the attacking keys to Alexis Sanchez upon his arrival in January. But with the Chilean a facilitator rather than a true forward, United became overly reliant on Romelu Lukaku. Sanchez monopolized the ball and sapped playing time away from Marcus Rashford and Anthony Martial. On top of all that, deficiencies without the ball nipped counterarracking potential in the bud.

Jose Mourinho has had a rough, complaint-filled summer at Manchester United ahead of the 2018-19 Premier League season. (Getty)

There is undoubtedly quality in the squad. There are identifiable ways to improve in between the penalty boxes, boost the underlying output and make another 80-something points attainable. But is Mourinho the man to do that? Is he in the mood to?

Mourinho himself would probably turn those questions around: Does he have the players to do so?

Man United’s strange summer

United dipped into Shakhtar Donetsk’s Brazilian pipeline to buy Fred, who could slot into midfield alongside Pogba and Nemanja Matic to solve the skill set-role mismatch. Or he could be ordinary and inconsequential. And that’s the problem: United’s only non-teenage, non-reserve keeper signing of the summer is an unknown quantity.

“I would like to have two more players. I think I’m not going to have two,” Mourinho said in Michigan, offering a window into behind-the-scenes discord. “I think that it’s possible that I’m going to have one. I gave a list to my club of five names a few months ago, and I wait to see if it’s possible.”

At least one of those players must be a central defender. United has been linked with both Toby Alderweireld and Harry Maguire. At time of writing, it has landed neither.

That, in part, is why Mourinho’s relationship with CEO Ed Woodward is reportedly at an “all-time low.”

And that, in part, is why many are wondering whether Mourinho will even last another nine months at Old Trafford.

Are Mourinho and United careening toward a breakup?

Woodward and the United board, to some extent, have no choice but to stand by Mourinho. They signed off on a contract extension in January. But they have players to stand by as well.

As the figurehead, Mourinho’s snarly mood becomes pervasive and virulent. A week after Pogba led France to a World Cup title, Mourinho claimed the disparity between Pogba’s national team performances and his club performances was not “about us getting the best out of him,” but rather “about him giving the best he has to give.” He intimated that Pogba tended to “lose concentration” with United.

Less than a week later, in an interview with the club’s own in-house TV channel, he took issue with Martial for spending extended time away from the squad for the birth of his child.

Pogba and Martial are arguably United’s two most talented players. Now both reportedly want to leave.

The friction is reminiscent of Mourinho’s calamitous, truncated final act at Chelsea, when he seemingly butted heads with half the squad. That third season, also preceded by a contract extension, ended in December, when Mourinho left a title-winning team hovering just above the relegation zone.

The 55-year-old has never spent more than three full seasons at one club. Ahead of year three at United, we are once again seeing why. Jose The Grouch seems determined to extend the trend.

His history, and the fact that he was still living out of a Manchester hotel, fueled reports in January that he was months away from resigning. He stuck around, calling the reports “garbage.”But his frustrations with Woodward and the board have been festering. His complaints have been slowly crescendoing.

The writing is on the wall. And whenever it’s appeared in the past, Mourinho has never been inclined to scrub too hard.